Research and design of corporate networks infrastructure using SDN technologies with emphasis to virtual switch

Software Defined Networking has brought revolution to the world of Network technology which replaces most of the physical devices and control layer of the cloud computing reference model takes control of many Networking Devices. A Virtual Switch is a software by the virtue of which communication between several virtual machines take place. In contrast to physical switch is, it does not only forwards data packets but also checks the data for security before it is forwarded to other virtual machines. Interrelated components of software components work together to form a virtual network infrastructure. Out of the software components, the emphasis is targeted on Virtual switch functions and how it differs from the traditional switches

The Logarithmic Conformal Field Theories

We study the correlation functions of logarithmic conformal field theories. First, assuming conformal invariance, we explicitly calculate two-- and three-- point functions. This calculation is done for the general case of more than one logarithmic field in a block, and more than one set of logarithmic fields. Then we show that one can regard the logarithmic field as a formal derivative of the ordinary field with respect to its conformal weight. This enables one to calculate any $n$-- point function containing the logarithmic field in terms of ordinary $n$--point functions. At last, we calculate the operator product expansion (OPE) coefficients of a logarithmic conformal field theory, and show that these can be obtained from the corresponding coefficients of ordinary conformal theory by a simple derivation.Comment: 17 pages ,latex , some minor changes, to appear in Nucl. Phys.

Entanglement Entropy in a Non-Conformal Background

We use gauge-gravity duality to compute entanglement entropy in a non-conformal background with an energy scale $\Lambda$. At zero temperature, we observe that entanglement entropy decreases by raising $\Lambda$. However, at finite temperature, we realize that both $\frac{\Lambda}{T}$ and entanglement entropy rise together. Comparing entanglement entropy of the non-conformal theory, $S_{A(N)}$, and of its conformal theory at the $UV$ limit, $S_{A(C)}$, reveals that $S_{A(N)}$ can be larger or smaller than $S_{A(C)}$, depending on the value of $\frac{\Lambda}{T}$.Comment: 5 pages, 3 figures, published versio

Logarithmic N=1 superconformal field theories

We study the logarithmic superconformal field theories. Explicitly, the two-point functions of N=1 logarithmic superconformal field theories (LSCFT) when the Jordan blocks are two (or more) dimensional, and when there are one (or more) Jordan block(s) have been obtained. Using the well known three-point fuctions of N=1 superconformal field theory (SCFT), three-point functions of N=1 LSCFT are obtained. The general form of N=1 SCFT's four-point functions is also obtained, from which one can easily calculate four-point functions in N=1 LSCFT.Comment: 10 pages, LaTeX file, minor revisions made, to appear in Phys. Lett.

Phase Transition in a Self--Gravitating Planar Gas

We consider a gas of Newtonian self-gravitating particles in two-dimensional space, finding a phase transition, with a high temperature homogeneous phase and a low temperature clumped one. We argue that the system is described in terms of a gas with fractal behaviour.Comment: corrections made and discussions enlarged; to appear P.L.

Logarithmic conformal field theories with continuous weights

We study the logarithmic conformal field theories in which conformal weights are continuous subset of real numbers. A general relation between the correlators consisting of logarithmic fields and those consisting of ordinary conformal fields is investigated. As an example the correlators of the Coulomb-gas model are explicitly studied.Comment: Latex, 12 pages, IPM preprint, to appear in Phys. Lett.